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Query: UMLS:C0221002 (primary hyperparathyroidism)
 4,921 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We sought an explanation for prior findings of high plasma chromogranin-A (Chr-A) in primary hyperparathyroidism. Chr-A was measured in plasma samples from 55 controls and 73 patients with primary hyperparathyroidism caused by adenoma (n = 14), sporadic or familial hyperplasia (n = 10), or familial multiple endocrine neoplasia type 1 (FMEN1; n = 49). Serum or plasma samples were also tested for calcium, PTH, gastrin, pancreatic polypeptide, CG alpha, and PRL. Plasma Chr-A was 34 +/- 10 in parathyroid adenoma, 55 +/- 33 in parathyroid hyperplasia without FMEN1, 63 +/- 88 in FMEN1, and 25 +/- 8 in controls (mean +/- SD; nanograms per ml; FMEN1 or parathyroid hyperplasia vs. control, P less than 0.05). Plasma Chr-A did not correlate with other hormonal variables in controls. Plasma Chr-A correlated with log serum gastrin (r = 0.43; P = 0.003) and plasma PTH (r = 0.52; P less than 0.05) only in FMEN1. In FMEN1, plasma Chr-A was highest in subjects with Zollinger-Ellison syndrome (ZES, 120 +/- 127; no ZES, 30 +/- 33 (P less than 0.0001). Parathyroidectomy did not decrease plasma Chr-A in patients with parathyroid adenoma or parathyroid hyperplasia. For FMEN1 patients with available pre- and postparathyroidectomy samples, Chr-A decreased postoperatively in four of five patients with ZES compared to none of six patients without ZES (P less than 0.05). Elevated plasma Chr-A is not a general feature of primary hyperparathyroidism. Elevated plasma Chr-A in primary hyperparathyroidism was restricted principally to patients who also had ZES. Primary hyperparathyroidism may influence the level of Chr-A by an effect of hypercalcemia or elevated PTH on Chr-A secretion from pancreatic islet tissue.
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PMID:Plasma chromogranin-A in primary hyperparathyroidism. 257 19

Functioning parathyroid lipoadenoma (hamartoma) composed of abundant adipose or myxomatous stroma and epithelial cell nests is an unusual cause of primary hyperparathyroidism. We report herein four new cases. None of them belongs in the category of multiple endocrine neoplasia or familial hyperparathyroidism. The clinical manifestations and the laboratory findings are indistinguishable from those of the usual forms of primary hyperparathyroidism. Ultrasonography of the neck demonstrated an enlarged parathyroid gland as a hyperechoic mass in the two patients tested. At operation in each case, a single enlarged gland was found and resected, the weight being 3, 0.3, 0.45 and 1 g, respectively. The patients are normocalcemic 1 to 10 years after surgery. Pathological examination disclosed that the lesions were consistent with lipoadenoma or its variants. On reviewing 20 cases of functioning lipoadenoma which were reported in the literature, including the present cases, we found that the size of the tumors varied and a functioning lipoadenoma is hence by no means unusually large as previously reported. Without knowledge of this specific clinicopathologic entity, the lesion may be overlooked at the preoperative localization study and misdiagnosed as a normal or hyperplastic parathyroid.
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PMID:Functioning parathyroid lipoadenoma--report of four cases: clinicopathological and ultrasonographic features. 265 9

High-resolution, real-time sonography can be used to assess the size and location of the parathyroid glands. The authors review the types of information provided by sonography and outline the ways in which it contributes to the management of primary hyperparathyroidism. Sonography usually can differentiate parathyroid adenoma from hyperplasia. In milder cases, with less parathyroid enlargement, this differentiation is difficult but can be facilitated by determining three dimensions for each gland. Preoperative knowledge of the presumptive location of an adenoma is most useful when the strategy of unilateral neck exploration is to be used because it will allow the exploration always to begin on the correct side. Sonographic evidence of hyperplasia should trigger a preoperative search for multiple endocrine neoplasia and will alert the surgeon that a bilateral neck exploration and thymectomy will be needed. A more universal benefit is the ability to predict or exclude intrathyroidal and subcapsular parathyroid tumors, thus guiding the decision for thyroid versus thymic exploration in the event of a missing abnormal gland. Sonography often fails to visualize parathyroid tumors in an ectopic position away from the thyroid bed. Such tumors, however, may be anticipated when the sonogram shows only three enlarged glands in cases of hyperplasia, or only three glands of normal size in a patient with strong biochemical evidence of hyperparathyroidism. Because it is noninvasive and inexpensive and can provide a wealth of information, the authors have adopted sonography as a routine preoperative procedure for primary hyperparathyroidism.
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PMID:The role of parathyroid ultrasonography in the management of primary hyperparathyroidism. 266 86

Primary hyperparathyroidism is a common disorder and one that can usually (approximately 95%) be successfully treated by parathyroidectomy. PTH assays have become quite accurate for confirming the diagnosis. In patients with malignancy-associated hypercalcemia, parathyroid-like protein levels are usually increased, and radioimmunoassays being developed to quantitate serum levels of this protein will make the diagnosis easier. Treatment for a parathyroid adenoma is removal of the tumor and identification of the normal parathyroid glands. Treatment for primary or secondary hyperplasia is usually subtotal parathyroidectomy. Recurrent hyperparathyroidism is uncommon, except in patients with familial hyperparathyroidism, MEN-1 parathyroid carcinoma, or renal failure and secondary hyperparathyroidism. Persistent hyperparathyroidism is more common and is usually due to surgeon inexperience, but it is also caused by ectopically situated parathyroid glands, multiple abnormal parathyroid glands, or supranumerary parathyroid glands. Preoperative localization studies using ultrasound, thallium-technetium scanning, MRI, or CT scanning are reliable in patients with solitary parathyroid adenomas, but often fail to detect all of the abnormal parathyroid tissue in patients with multiple abnormal parathyroid glands. Intraoperative use of urinary cyclic AMP assays and rapid PTH assays have recently been used experimentally during parathyroid explorations to determine whether all hyperfunctioning parathyroid tissue has been removed, but these methods are not yet reliable or fast enough to be generally accepted. Most patients with primary hyperparathyroidism who are successfully treated by parathyroidectomy experience psychological, clinical, and metabolic benefits.
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PMID:Primary hyperparathyroidism. A surgical perspective. 267 68

We have extended our study of an incomplete variant of multiple endocrine neoplasia Type I (MEN IBurin). In this syndrome, primary hyperparathyroidism and prolactin-secreting adenoma are common, with hormone-secreting pancreatic tumors being rarely seen. The recent localization of the prolactin structural gene to chromosome 6 made further investigation of linkage to HLA of particular interest. Results in 2 multigeneration families exclude close linkage to HLA. We cannot at this time draw any inference regarding linkage of MEN IBurin to the prolactin structural gene.
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PMID:Variant multiple endocrine neoplasia I (MEN IBurin): further studies and non-linkage to HLA. 285 81

Serum calcium levels were analyzed after one or more explorations for primary hyperparathyroidism in familial multiple endocrine neoplasia type I. These data covered all 85 operations (performed in many hospitals) on 61 of 62 members from 14 kindreds. After 61 initial operations, there were high rates of persistent or recurrent hypercalcemia (54 percent) and chronic hypocalcemia (10 percent). These rates contrast with lower postoperative rates of hypercalcemia (4 to 16 percent) or chronic hypocalcemia (1 to 8 percent) in large series of primary hyperparathyroidism. Persistent or recurrent hypercalcemia after initial exploration decreased only modestly in patients who underwent surgery after 1975 versus before 1975 (46 versus 63 percent). The rate for long-term remission of hypercalcemia after initial parathyroidectomy was higher after a diagnosis of parathyroid hyperplasia was made (as opposed to adenoma) (57 versus 30 percent, p less than 0.05) and after removal of three or more glands (as opposed to removal of two and a half or less) (70 versus 34 percent, p less than 0.01). Following 24 reoperations, there were also high rates of persistent or recurrent hypercalcemia (46 percent) and chronic hypocalcemia (25 percent). After surgery in unselected patients with primary hyperparathyroidism, recurrent hypercalcemia (as opposed to persistent hypercalcemia) is distinctly uncommon; however, it was frequent in familial multiple endocrine neoplasia type I, with total recurrences increasing from 21 percent at five years to 41 percent at 10 years in patients who showed a normocalcemic interval after surgery. The data indicate that the occurrence of persistent or recurrent hypercalcemia after parathyroidectomy in familial multiple endocrine neoplasia type I remains frequent. Although recurrent hypercalcemia may be characteristic of the response to any technique of parathyroidectomy in familial multiple endocrine neoplasia type I and not preventable, persistent hypercalcemia can be decreased by preoperative recognition of the specific familial cause, involvement of an experienced surgical team, and histologic confirmation of the identification of three or more parathyroid glands.
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PMID:Primary hyperparathyroidism in familial multiple endocrine neoplasia type I. Long-term follow-up of serum calcium levels after parathyroidectomy. 285 57

A family of multiple endocrine neoplasia type I with five confirmed cases in three generations is described. All of them have primary hyperparathyroidism in common. The propositus is 51 year-old male. After a year of symptoms of gastroduodenal ulcer, he was found to have elevated levels of serum gastrin and PTH. The serial imaging studies revealed a tumor in pancreatic head, and Zollinger-Ellison syndrome was diagnosed. The gastrin level was reduced into normal range after extirpation of the tumor, but post surgical elevation of Calcium put the patient under parathyroidectomy, which normalized serum PTH and Calcium levels. His two sisters (I and II), the mother of them, and the daughter of sister I, had neither signs nor symptoms until family study showed hypercalcemia in all. Sister I is a 54 year-old female with enlarged parathyroid. The hyperparathyroidism is of chemical type, but no other endocrinological abnormality is found. The Calcium level decreased after parathyroidectomy. Sister II is a 56 year-old female. The only sign was galactorrhea. Serum PTH and Calcium decreased after parathyroidectomy. The prolactinoma was diagnosed by the increased prolactin levels and enhanced mass lesion in sella turcica. Her serum prolactin levels is now within normal range since she is on bromocryptine. The mother of the above three siblings and the daughter of the sister I are now under further study.
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PMID:[A family with multiple endocrine neoplasia type I presenting prolactinoma, Zollinger-Ellison syndrome and hyperparathyroidism]. 286 39

In patients with hypercalcemia with abdominal symptoms, gastrin concentration is often measured to exclude the Zollinger-Ellison syndrome. We found that interpretation of such measurements is clouded by a contradictory literature. We therefore measured serum gastrin concentrations in 78 patients with primary hyperparathyroidism, 36 with nonparathyroid hypercalcemia, 13 with hypocalcemia, and 33 normocalcemic controls. Gastrin values above normal occurred in 22% of those with primary hyperparathyroidism and 28% of those with nonparathyroid hypercalcemia. Values above 250 pg/mL occurred only in those with hypochlorhydria or multiple endocrine neoplasia, type 1 (MEN 1). After parathyroidectomy, gastrin levels fell significantly, but elevated values tended to recur in those with MEN 1 if hypercalcemia recurred. Thus, chronic hypercalcemia of either parathyroid or nonparathyroid origin may elevate serum gastrin concentrations, but marked elevations suggest either achlorhydria or MEN 1.
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PMID:Serum gastrin level is increased by chronic hypercalcemia of parathyroid or nonparathyroid origin. 286 39

Hyperplasia of the parathyroid glands is a central feature of familial multiple endocrine neoplasia type 1. We used cultured bovine parathyroid cells to test for mitogenic activity in plasma from patients with this disorder. Normal plasma stimulated [3H]thymidine incorporation, on the average, to the same extent as it was stimulated in a plasma-free control culture. This contrasted with the results of the tests with plasma from patients with familial multiple endocrine neoplasia type 1, in which parathyroid mitogenic activity increased 2400 percent over the control value (P less than 0.001). Plasma from these patients also stimulated the proliferation of bovine parathyroid cells in culture, whereas plasma from normal subjects inhibited it. Parathyroid mitogenic activity in plasma from the patients with familial multiple endocrine neoplasia type 1 was greater than that in plasma from patients with various other disorders, including sporadic primary hyperparathyroidism (with adenoma, hyperplasia, or cancer of the parathyroid), sporadic primary hypergastrinemia, sporadic pituitary tumor, familial hypocalciuric hypercalcemia, and multiple endocrine neoplasia type 2 (P less than 0.05). Parathyroid mitogenic activity in the plasma of patients with familial multiple endocrine neoplasia type 1 persisted for up to four years after total parathyroidectomy. The plasma also had far more mitogenic activity in cultures of parathyroid cells than did optimal concentrations of known growth factors or of any parathyroid secretagogue. This mitogenic activity had an apparent molecular weight of 50,000 to 55,000. We conclude that primary hyperparathyroidism in familial multiple endocrine neoplasia type 1 may have a humoral cause.
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PMID:Parathyroid mitogenic activity in plasma from patients with familial multiple endocrine neoplasia type 1. 287 88

We measured multiple components of serum or plasma in 221 members of a kindred with familial multiple endocrine neoplasia type 1 (FMEN1). The kindred showed typical features of FMEN1; the FMEN1 gene could be traced through 7 generations with 74 members identifiable as gene carriers. Between family screening in 1981 and completion of our study in 1985, we identified 16 previously unscreened members as carriers of the FMEN1 gene. The earliest age at diagnosis of FMEN1 was 17. The tests with the greatest yield of abnormal results among carriers of the FMEN1 gene were albumin-adjusted calcium, PTH, gastrin, and (in females) prolactin. The following tests provided little or no use in identifying carriers: prolactin (in males), pancreatic polypeptide, glucagon, glicentin, insulin, growth hormone, motilin, and somatostatin. Primary hyperparathyroidism was the commonest expression of the FMEN1 gene; the gene penetrance for this trait increased from near 0% before age 15 to near 100% after age 40. It appeared prior to development of serious morbidity from hypergastrinemia or hyperprolactinemia. All 42 co-operating members who were alive and expressing the FMEN1 gene in 1984 showed active or treated primary hyperparathyroidism. Primary hypergastrinemia had a prevalence below half of that for primary hyperparathyroidism at all ages and was not diagnosed in the absence of primary hyperparathyroidism. Primary hyperprolactinemia was still less prevalent than primary hypergastrinemia. It was limited almost exclusively to females.
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PMID:Multiple endocrine neoplasia type I: assessment of laboratory tests to screen for the gene in a large kindred. 287 98


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